Stabilizing and snubbing mechanism for gyratory extractors



May 22, 1956 FOSTER 2,746,568

STABILIZING AND SNUBBING MECHANISM FOR GYRATORY EXTRACTORS Filed March 29, 1952 2 Sheets-Sheet l INVENTOR. FIE 4 JZMe-s 1a FOSTER QMLWJ 3/ 4r ORA/E ya STABILIZING AND SNUBBING MECHANISM FOR GYRATORY EXTRACTORS James R. Foster, Webster City, Iowa, assignor, by mesne assignments, to Gamble-Skogmo, Inn, Minneapoiis, Minn., a corporation of Delaware Application March 29, 1952, Serial No. 279,304

3 Claims. (Cl. 188-4) This invention relates generally to improvements in snubbers or dampers for gyrating mechanisms, and particularly for domestic clothes washing machines of the type wherein the clothes are washed and then dried by a centrifuging action. This general type of machine is disclosed in the George P. Castner et a1. U. S. Patent No. 2,513,844 and this patent also shows the general type of snubbing mechanism which I am to improve in accordance with my present invention. Attention is also called to the co-pending application of George P. Castner, Serial No. 258,710, filed November 28, 1951, for Snubbing Mechanism for Gyrating Extractors, as also showing the general type of snubber or stabilizer with which I am concerned.

As disclosed in detail in these prior disclosures, the problem is to damp or snub the gyrations of the inside frame-receptacle assembly, when the receptacle is set in motion to centrifugally extract the washing or rinsing liquid. This assembly is mounted for tilting movement about a lower end support or bearing so that the spinning receptacle may gyrate when the load therein is out of balance, as it almost invariably is when centrifuging begins. Such gyratory movement is damped by the provision of a heavy balancing ring upon the receptacle assisted by a centering and frictionally snubbing mechanism which tends to center the assembly on the spin axis and frictionally resist any movements of the assembly away from that axis. It is the primary object of my invention to improve this frictional snubbing mechanism, to simplify and facilitate its manufacture, assembly and servicing, and to improve its damping efiect on the gyrating mechanism to the point where smoother operation is possible than present in the previous mechanisms, or alternatively, to achieve an equal smoothness and effectiveness of operation while reducing the necessary weight of the remaining component of the stabilizing means, i. e., the balancing ring, with a resulting further decrease in manufacturing costs.

Another object of my invention is to improve the'construction and arrangement of the parts adjacent to and constituting the lower part of the gyrating assembly, be low the receptacle, and to so group and concentrate them around a downward extension of the spin axis, that this assembly will have a static imbalanced condition such that it may be counteracted by a single centering spring, as contrasted with the several centering springs of the earlier disclosures, to thus effect a further saving.

Still another object is to provide an improved friction snubbing or damping mechanism per se, providing smoother, more effective stabilization and of such nature as to materially facilitate manufacture and assembly.

These and other more detailed and specific objects will be disclosed in the course of the following specification, reference being had to the accompanying drawings, in which- Fig. 1 is a horizontal sectional view through and plan view of the lower portion of a clothes washing machine,

* United States Patent with which is associated my improved snubbing mechanism.

Fig. 2 is a sectional and side elevational view, on a reduced scale as taken substantially on the plane 2-2 in Fig. 1.

Fig. 3 is an enlarged vertical, radial section along the line 3-3 in Fig. 1.

Fig. 4 is a detail, perspective and fragmentary view of a part of the snubbing mechanism.

Fig. 5 is a detached elevational view of one of the snubber spring retainers or cross arms.

Referring now more particularly and by reference characters to the drawings, the clothes washing machine chosen as an example to illustrate the application of my invention comprises a main, stationary outside frame, designated generally at A, having a bottom channel B supported by feet C and an outer skirt or wrap-around D in accordance with the usual practice in this type of construction. A bearing cup E connected by spider F to the bottom channel B tiltably supports an inside frame assembly, designated generally at G, which gyrates about this support under the influence of unbalanced load conditions in the clothes receptacle H, which surmounts the inside gyrating assembly and is located above a partition forming the bottom of the splash tub I. Legs I support the splash tub I and other upper parts of this stationary frame assembly and secured to these legs immediately below the splash tub is a top ring K of channel shaped cross section as shown.

The machine here shown employs a single electric motor for washing and centrifuging, by contrast with the two motors of U. S. Patent No. 2,513,844, this single motor appearing at L and being supported on a part of the inside frame assembly G which is carried in the bearing cup E. Mounted on the upper end of the vertical motor shaft is a fluid coupler M of the kind set out in the earlier Castner patent and this coupler spins the receptacle H through a belt N and pulleys O. A clutch selectively disables the drive from motor shaft to fluid coupler. Another pulley P on the motor shaft operates a conventional transmission unit Q through a belt R and pulley S and this transmission unit, also carried by assembly G, converts rotary to oscillating motion to drive the conventional agitator (not shown) in the receptacle H. Actually as seen in Fig. l the belt R drives a pump pulley R and another belt R in turn drives the transmission. Clutch mechanism selectively disables the drive between transmission and agitator so that the latter may be stopped after the washing action is completed and as the receptacle is set in spinning rotation for extracting the liquid from the clothes. When the load in the receptacle is unevenly distributed about the spin axis gyration of the inside assembly and the receptacle takes place, during which this assembly tilts in the bearing cup E, and these gyrations must, of course, be controlled and the resulting vibrations absorbed or damped out for satisfactory operation of the machine. Not shown here but found in both or" the earlier disclosures heretofore identified is a heavy balancing ring which surmounts the receptacle H to assist in balancing and controlling the gyratory movement but in addition centering and frictionally snubbing mechanism is also necessary.

As in the earlier disclosures such centering and stabilizing mechanism is arranged between the outside frame A and inner gyrating assembly G, below the splash tub I, and as here shown comprises three radially extending snubber arms 10 of flexible or spring material, and secured at inner ends by screws 11 to a horizontal flange 12 forming part of assembly G. These arms ill radiate outwardly and at outer ends they overlie brackets or boxes, designated generally at 13, which are secured at appropriate locations around the ring K. Each such -inturncd flanges K of the base ring K and are secured thereto by elongated bolts 17 passing downward through the flanges, as best seen in Fig. 3. Thus each of these brackets is boxed in or closed on four sides and open only at the ends. The outer ends of the snubber arms 10, where they overlie the brackets 13, are widened, or paddle-shaped, as seen at 18 and secured to the underside of each such widened end is a spaced pair of rectangular snubber shoes 19, held in place by suitably countersunk rivets 20 and bearing downward on the smooth upper surface of the adjacent brackets upper-flange 14. The shoes 19 are spaced apart from the radial center line of the snubber arms and between the shoes each arm is provided with a spring opening 21 and the upper flange 14 with a larger, clearance opening 22. At each bracket, then, there is provided a snubber or hold down spring 23 of the retractile, coil variety having an upper end 24 extending upwardly through the registering openings 21 and 22 and provided thereabove with a hook 25. Extending crosswise of each snubber arm is a bridge or cross arm 26 formed up from sheet material with an arcuate cross section (Fig. 3) over most of its length and spanning the openings 2122. At its center each said cross arm 26 is notched at 27 and grooved to engage and locate the hook 25 of the spring. Extending along opposite edges of each cross arm 26 are outwardly turned flanges or lips 28 which bear on the upper surface of the snubber arms 10, but said flanges terminate at 29 short of the opposite ends of the cross arms (Fig. 4) so that outwardly the cross arms may be formed with downturned lugs 30 which fit into lateral notches 31 formed in the outer ends 18 of the snubber arms and lock the cross arms thereto.

The lower end 32 of each spring 23 extends loosely through a clearance opening 33 in the lower flange 15 of the bracket and below said flange has a hook 34. This hook is engaged at the center of an identical but inverted bridge or cross arm 26 ,.the end lugs 30 of which are turned upwardly and engaged in suitable slots 35 provided for their reception in said lower flange 15. It will be noted that the springs 23 all stand exactly vertically when the gyrating assembly G is in its normal, centered position.

In accordance with my invention the motor, transmission, pump, clutch and other driving parts forming part of assembly G are all grouped as closely as possible about the vertical center line V, which is a downward extension of the spin axis of receptacle H and is the line from which gyratory deflections originate. Thus the offcenter static load is reduced but even so the weight of the motor C tends to give the assembly a static imbalance such that it tends to move off to the right as viewed in Fig. 2. This tendency is counteracted and static balance restored by a single centering spring 36, of the retractile coil variety, which is stretched between the base ring K and one of the fastenings H of the snubbing arm opposed to the motor, or at the opposite side of the machine with reference to the motor. The outer end 37 of said spring 36 is adjustably connected by an eye-bolt 38 to said ring K so that the effective tension of the spring may be adjusted to properly center and balance the gyrating assembly.

Operation Any tilting movement of the inner assembly G in any direction as gyration begins will now be seen to be accompanied by a relative movement of the snubber arms 10 with respect to the brackets 13. The down pull of the springs 23 holding the snubber shoes 19, which are of belting or analogous material, down frictionally against the brackets will, of course, frictionally resist such movement thus to snub or damp the gyrating motion. Since all of the springs extend vertically in the normal, centcrcd position of the assembly, gyrating movement in any direction will be snubbed by all three springs to maintain an even, smooth damping action under all conditions. It is important to note that the cross arms 26-26 are, respectively, bowed or arched upwardly and downwardly at their centers. Thus the pull of the springs 23 will be brought out to and concentrated immediately against the shoes 19 to insure even braking and snubbing action thereof. These cross arms 26-26 also will take the wear of the hooked ends of the springs 23 as they rock in all directions and the cross arms may be easily and comparatively inexpensively replaced when they become worn. The boxed-in location of the springs, enclosed as they are on four sides by the brackets 13 and ring K, protects them against damage or displacement when service work is being done on other parts of the machine.

The single centering spring 36 not only results in a saving in initial cost and upkeep as compared to the plurality of springs in the earlier disclosures but makes it easier to center the gyrating assembly with only the one adjustment necessary for this purpose. Withal the snubbing mechanism as here presented is found in practice to operate much more effectively and smoothly than the prior mechanisms and it is possible to materially reduce the weight of material used in the balancing ring atop the receptacle while maintaining a more than adequate snubbing and stabilizing action with the mechanism according to my invention.

It is obvious that the snubber shoes on the snubber arms could cooperate with the under surface of the lower flange of the bracket instead of the top surface of the upper flange in exactly the same manner, and this cooperation is therefore not limited to the upper flange.

It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

i 1. In a snubbing mechanism for a centrifugal extractor having an outer frame and an inner frame and the latter supporting a clothes receptacle for spinning rotation about an upright axis, and means supporting said inner frame and receptacle for gyration about the spin axis when the receptacle is rotated in an unbalanced condition, and having a plurality of vertically flexible snubber arms annularly spaced between the inner and outer frames and rigidly secured to the inner frame and .extending outwardly toward the outer frame for snubbing contact with a horizontal friction surface on a part fixed to the outer frame, and a normally vertically extending spring between the frame and the outer end of each arm for increasing the snubbing friction as the inner frame with the snubber arms is displaced in any direction; the improved assembly of the friction elements for each arm comprising a box-shaped bracket having upper and lower flanges secured to the outer frame, one of said flanges providing on its outer side the friction surface, the overlapping snubber arm having friction shoes slidable on said surface, the snubber arm and said upper and lower flanges having openings, said vertical spring being arranged between said flanges and having its ends extending loosely through said openings, and a separate but identically formed cross arm engaged by each end of said spring and bearing on the snubber arm and the outer surface of the other flange respectively, each of said cross arms being bowed between its ends and grooved at its center for engagement by the corresponding spring end.

2. In a snubbing mechanism for a centrifugal extractor having an outer frame and an inner frame and the latter supporting a clothes receptacle for spinning rotation about an upright axis, and means supporting said inner frame and receptacle for gyration about the spin axis when the receptacle is rotated in an unbalanced condition, and having a plurality of vertically flexible snubber arms annularly spaced between the inner and outer frames and rigidly secured to the inner frame and extending outwardly toward the outer frame for snubbing contact with a horizontal friction surface on a part fixed to the outer frame, and a normally vertically extending spring between the frame and the outer end of each arm for increasing the snubbing friction as the inner frame with the snubber arms is displaced in any direction; the improved assembly of the friction elements for each arm comprising a box-shaped bracket having upper and lower flanges secured to the outer frame, one of said flanges providing on its outer side the friction surface, the overlapping snubber arm having friction shoes slidable on said surface, the snubber arm and said upper and lower flanges having openings, said vertical spring being arranged between said flanges and having its ends extending loosely through said openings, and a separate but identically formed cross arm engaged by each end of said spring and bearing on the snubber arm and the outer surface of the other flange respectively, each of said cross arms being bowed between its ends and grooved at its center for engagement by the corresponding spring end, said cross arms further having lugs, and the snubber arms and brackets having similarly spaced notches to receive said lugs and hold the cross arms against displacement.

3. In a snubbing mechanism for a centrifugal extractor having an outer frame and an inner frame and the latter supporting a clothes receptacle for spinning rotation about an upright axis, and means supporting said inner frame and receptacle for gyration about the spin axis when the receptacle is rotated in an unbalanced condition, and having a plurality of vertically flexible snubber arms annularly spaced between the inner and outer frames and rigidly secured to the inner frame and extending outwardly toward the outer frame for snubing contact With a horizontal friction surface on a part fixed to the outer frame, and a normally vertically extending spring between the frame and the outer end of each arm for increasing the snubbing friction as the inner frame with the snubber arms is displaced in any direction; the improved assembly of the friction elements for each arm comprising a box-shaped bracket having upper and lower flanges secured to the outer frame, one of said flanges providing 011 its outer side the friction surface, the overlapping snubber arm having friction shoes slidable on said surface, the snubber arm and said upper and lower flanges having openings, said vertical spring being arranged between said flanges and having its ends extending loosely through said openings, and a separate but identically formed cross arm engaged by each end of said spring and bearing on the snubber arm and the outer surface of the other flange respectively, each of said cross arms being bowed between its ends and grooved at its center for engagement by the corresponding spring end, said cross arms further having lugs, and the snubber arms and brackets having similarly spaced notches to receive said lugs and hold the cross arms against displacement, said vertical spring having identical upper and lower hooked ends extending through said openings, the cross arms traversing said openings on the outside of said snubber arms and said other flange being engaged by the hooked ends of the spring.

References Cited in the file of this patent UNITED STATES PATENTS 2,396,105 Kirby Mar. 5, 1946 2,454,112 Woodson Nov. 16, 1948 2,513,845 Castner July 4, 1950 2,534,194 Emmert et a1. Dec. 12, 1950 2,585,107 Geldhof Feb. 12, 1952 FOREIGN PATENTS 606,855 Germany Dec. 12, 1934 

